/**
 * Copyright (c) 2008, Mu Dynamics.
 *  All rights reserved.
 *  
 *   Redistribution and use in source and binary forms, with or without modification, 
 *   are permitted provided that the following conditions are met:
 *   
 *  - Redistributions of source code must retain the above copyright notice, 
 *     this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright notice, 
 *     this list of conditions and the following disclaimer in the documentation and/or 
 *     other materials provided with the distribution.
 *  - Neither the name of the "Mu Dynamics" nor the names of its contributors may be used 
 *     to endorse  or promote products derived from this software without specific prior 
 *     written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.mu.jacob.core.renderer;

import java.io.File;
import java.io.StringWriter;
import java.io.Writer;

import com.mu.jacob.core.generator.GeneratorException;

import freemarker.cache.FileTemplateLoader;
import freemarker.cache.MultiTemplateLoader;
import freemarker.cache.TemplateLoader;
import freemarker.template.Configuration;
import freemarker.template.DefaultObjectWrapper;
import freemarker.template.Template;

/**
 * Freemarker renderer
 * 
 * @author Adam Smyczek
 */
public class FreeMarkerRenderer extends AbstractRenderer {

	/* Freemarker config */
	private Configuration configuration;
	
	/* Global template group */
	private File globalTemplateGroup = null;
	
	/**
	 * Set global template group path
	 * @param globalTemplateGroup
	 */
	public void setGlobalTemplateGroup(final File globalTemplateGroup) {
		if ((globalTemplateGroup != null) && globalTemplateGroup.exists()) {
				this.globalTemplateGroup = globalTemplateGroup;
		}
	}

	/**
	 * @see com.mu.jacob.core.renderer.IRenderer#render(java.io.File)
	 */
	public String render(File templateFile) throws Exception {
		initEngine();
		Template template= getConfiguration().getTemplate(templateFile.getName());  
		Writer writer = new StringWriter();
	    template.process(getContextMap(), writer);
	    return writer.toString();
	}

	/**
	 * Initialize freemarker
	 */
	@Override
	protected void initEngine() {
		configuration = new Configuration();
		try {
			if (globalTemplateGroup != null) {
				FileTemplateLoader gloablTemplateLoader = new FileTemplateLoader(globalTemplateGroup);
				FileTemplateLoader rootTemplateLoader = new FileTemplateLoader(getTemplateRoot());
				MultiTemplateLoader multiLoader = new MultiTemplateLoader(
						new TemplateLoader[] { gloablTemplateLoader, rootTemplateLoader });

				getConfiguration().setTemplateLoader(multiLoader);
			} else {
				getConfiguration().setDirectoryForTemplateLoading(getTemplateRoot());
			}
		} catch (Exception e) {
			throw new GeneratorException("Cannot configure FreeeMarker renderer!", e);
		}
		configuration.setObjectWrapper(new DefaultObjectWrapper()); 		
	}

	/**
	 * @return freemarker configuration
	 */
	protected Configuration getConfiguration() {
		return configuration;
	}

}
